Incarcerated women are often affected by childhood abuse, violence, and other difficult life circumstances throughout their life course, and typically come from disproportionately disadvantaged neighborhoods. However, relatively less research has examined how neighborhood characteristics and incarceration interact with inmates'risk factors. Although several criminal justice studies demonstrated that excessive incarceration may exacerbate community disadvantages and instability as a large proportion of residents constantly move between jail and community, the impact of neighborhood disadvantages on inmates'health outcomes, such as drug use and sexual risks have not been examined. Furthermore, while the rate of female incarceration has steadily increased over the past 20 years, previous studies predominantly concern with men, and women's unique life trajectories of incarceration, sexual risks, and drug use have been less understood. The study proposes to examine the impact and consequences of incarceration on the patterns of substance use, risky sexual behaviors, and recidivism among female inmates who are returning to the community from a large urban jail. The proposed conceptual model will be tested explaining the ecological factors associated with incarceration, and the impact of incarceration on drug use, STls/HlV risks, and recidivism among female inmates. To achieve the objectives, the proposed study will conduct: 1) qualitative in-depth interviews with women in jail exploring their experience with incarceration, changes in social networks and support, health concerns, health care and social services utilization, expected challenges upon release, and needs for successful transition to community life;2) face-to-face longitudinal surveys with a cohort of female inmates at three time points (baseline in jail, and two weeks and three months post-release) to examine primary outcomes (relapse to drug use, risks for STIs/HlV infection, recidivism), secondary outcomes, and mediators (social network, social support);and 3) multi-level analysis and mapping to explore the effects of neighborhood disadvantage and instability, the rates of incarceration and STIs on women's outcomes.